Kabushiki Kaisha Toshiba

Yukio Tsuda

Fumio Owada

Michihisa Iguchi

Nobuhiro Inoue

Akira Nakano

Katsunari Sasaki

Masayoshi Aihara

Toshiro Nose

In a recording apparatus for performing electro-static recording using toner, an image forming apparatus has a process unit including, as one unit, at least a photosensitive member and a spent toner holding section, a first counter for counting a total amount of use of the photosensitive member and a second counter for counting a total amount of toner that has been consumed. A determining section using the process unit determines the necessity for the process unit to be replaced with a new process unit by comparing a total amount of use of the photosensitive member counted by the first counter with a first predetermined reference value and the total amount of consumed toner with a second predetermined reference reference value according to whether the total amount of use of the photosensitive member exceeds the first reference value or the total amount of toner counted exceeds the second reference value.

Image forming apparatus using a process unit

A thermal head is used on a thermal transfer recording apparatus which can record a continuous, fine line or curve by recording many dots, by a thermal transfer system, on a recording sheet. The thermal head comprises a one-dimensional array of heat generation element groups each comprised of a plurality of heat generation elements, such as heat generation resistors of, for example, a parallelogram, a diamond or an elliptic configuration, continuously arranged in a direction perpendicular to that in which recording is made on a recording sheet and lead electrodes connected adjacent to each other in predetermined positions, in which the longitudinal sides of the heat generation resistors are made oblique at a predetermined angle.

Thermal head and thermal transfer apparatus

An electrophotographic recording device comprises a photoconductive drum which is rotated at a constant speed, a charger for charging a photoconductive surface of the photoconductive drum, a recording head which includes a large number of light emitting diodes arranged in a line, and which exposes the charged photoconductive surface, in order to form an electrostatic image corresponding to image data on the photoconductive surface, a developing unit for developing the electrostatic image into a toner image, a transfer unit for transferring the toner image onto a paper sheet, a fixing unit for fixing the toner image transferred onto the paper sheet, a line density decision circuit for deciding the line density of an image from the image data, and an emission time setting circuit for determining an emission time of the light emitting diodes in accordance with the line density detected by the decision circuit, the emission time setting circuit determining a first emission time in relation to image data to be printed with a first line density, and determining a second emission time shorter than the first emission time in relation to image data to be printed with a second line density higher than the first line density.

Electrophotographic recording device

An electrophotographic recording apparatus includes an exposing device for exposing a photosensitive member according to image data, a developing device for developing an electrostatic latent image created on the exposed photosensitive member, and a fixing device for fixing the developed image, and the exposing device includes an image data processing circuit for converting discontinuous black-level pixels included in the pixels of the image data which is constructed by a plurality of pixels selectively including black-level pixels and white-level pixels to a white level to create processed image data, and a line scanner for line-scanning the photosensitive member by a plurality of times according to the image data and the processed imaged data each time an image of one line is created so as to create an electrostatic latent image corresponding to a combination of the image data and the processed image data on the photosensitive member.

Electrophotographic recording apparatus and method capable of recording

A circuit switching system for switching a circuit from a telephone to a facsimile. Circuit switching is performed by a signal, designating circuit switching delivered to the circuit. The circuit is monitored. When a signal designating circuit switching is detected from the circuit, the circuit is switched automatically from the telephone to the facsimile and a starting signal is applied to the facsimile.

Circuit switching system

A laser printer comprises two reference clock generators to define the rotational speed of a polygon mirror (main scanning rotational mirror); namely, a first reference clock generator which generates a clock signal whose frequency is set so as to correspond to a scanning line density for a millimeter system, and a second reference clock generator for generating a clock signal whose frequency is set so as to correspond to a scanning line density for an inch system. One of these clock generators is selected in accordance with the scanning line density of received image data. As the rotational speed of the polygon mirror decreases, a decrease and an increase in the image data density occur in the directions of main- and sub-scan, respectively, whereas as the rotational speed of the polygon mirror increases, an increase and a decrease in the image data density occur in the directions of main- and sub-scan, respectively.

Laser printer with clock polygon control for inches and millimeters

A system preprocesses analog picture image signals formed by scanning a manuscript prior to binarization into signals representing black or white according to a predetermined threshold value, compares a digital signal of a picture element to be corrected and of a signal of a picture element at least one main scanning line before the picture element to be corrected and positioned at the same position as the picture element to be corrected in an auxiliary scanning direction which is attenuated with each main scanning line or lines are compared. The one of these two signals having a larger level at a given time is used as a reference signal showing the nature of tone of the manuscript. When the level of digital picture image signal of the picture element to be corrected is closer to a black or white than the level of the reference signal, the level of the digital picture image signal is adjusted towards black or white. In other cases, the level of the digital picture image signals is maintained. By this operation, the nature of tone of the manuscript is emphasized and the accuracy of judgement in later binarizing the analog picture image signals is improved.

Binarizing system of picture image signals

In a binarizing system wherein analog picture image signals produced by scanning a manuscript picture image is quantized and the quantized signals are converted into digital picture image signals which are binarized into signals representing black or white according to a predetermined threshold value, some picture image signals of picture elements on the same main scanning line as a picture element to be corrected and positioned before the picture element to be corrected among the digital picture image signals are selectively extracted, and at least one of the picture image signals whose level becomes a maximum or a minimum is further selected from the extracted picture image signals. The picture image signal thus selected is used as a reference signal showing the nature of tone of the manuscript picture image for subjecting the picture image signal of the picture image to be corrected to a calculation emphasizing the nature of tone of the picture image to be corrected in the manuscript picture image.

Growing community of inventors

Tokyo, Japan

Yukio Tsuda